Core taking apparatus



prall 3U, H935. F. THRIFT E999y428 CORE TAKING APPARATUS Filed March 27,1955 Patented Apr. 30, 1935 IUNITED STATES PATENT o1=1=1cl.:'fv

CORE TAKING APPARATUS Fred Thrift, Campbellton, Tex.

Application March 27,

3 Claims.

This invention relates to core taking apparatus. An object of theinvention is to provide apparatus of the character described for takingcores or samples of the formation encountered during well drillingoperations and embodies a core barrel with novel means whereby the samemay'be securely landed in position in, and securely maintained inposition in, the drilling apparatus.

Another object is to provide novel means for locking the core barrel inposition which may be readily released when it is desired to withdrawthe core barrel.

A further object is to provide, in a device of the character described,a novel construction whereby the drilling uid may be utilized to forcethe core barrel into its final position in the drill stem and drill andwhereby the pressure of the drilling uid is released when the corebarrel has landed in home position to indicate to the operator that theapparatus is in position for taking a core or sample.

Another object of the invention is to provide a sample taking devicethat may be readily lowered into and withdrawn from the drillingapparatus without withdrawing said -drilling apparatus from the Well. Y

With the above and other objects in view the invention has particularrelation to certain novel features of construction, operation andarrangement of parts an example of which is given in this specificationand illustrated in the accom panying drawing wherein:

Figure 1 shows a fragmentary vertical sectional view of a drill stemshowing the upper end of the core taking apparatus therein.

Figure 2 shows a vertical sectional view of the intermediate portionthereof, and

Figure 3 shows a vertical sectional view of the drill as attached to thelower end of the drill stem showing the lower end of the core barrel inhome position therein.

Referring now more particularly to the drawing wherein like numerals ofreference designate similar parts in each of the figures, the numeral 1designates a tubular drill stem whose sections are connected by suitabletool joints as 2 and attached to the lower. end o f the drill stem thereis a drill 3 of any conventional construction and having an axial bore 4through the lower end thereof for the inlet of thev sample. Above itslower end the bore 4 is reduced in diameter forming the seat 5 toreceive and support the lower end of the tubular core` barrel 6. Thelower end of the core barrel has sample retaining means 1933, serial No.663,054

(ci. Z55- 72) of any conventional construction. As shown the coreretaining means comprise exible fingers 'l whose lower ends are securedto the lower end of the core barrel and whose upper ends are curvedinwardly.

'Ihere is a stem 8 whose lower end is enlarged forming the plunger 9 andthe lowe:` end of this plunger is connected to the'upper end of said..ybarrel preferably by threads. This plunger andv the upper end of saidbarrel t closely within the cylinder I0 whose upper end is screwed intothe tool joint above. Beneath the upper end of the core barrel, saidbarrel is provided with the lateral openings II and within the barrelbeneath said openingsz there is the annular valve seat I2 pinned in saidbarrel by the pin I3 or otherwise secured therein. The seat is normallyclosed by means of the upwardly opening ball valve I4. v

The upper end of the stem 8 is enlarged and formed into an anchor I5,which is slidable` in the trip sleeve I6. The lower end of this sleevehas the vertically elongated slots I'l, I1 and a pin I8 extends throughsaid anchor and its ends lmove in said slots. The upper end of theanchor I5 has an upwardly diverging bearing I9 which terminates in thetransverse slot 20 through said anchor. There are the upwardly divergingflexible dogs 2|, 2I whose lower ends are seated in said bearing andpinned therein by the pin 22 and whose upper ends diverge out throughsaid slot 20. A coil spring 23 is located between the upper ends of saiddogs.

The numeral 24 designatesa rod whose lower end is formed into a plunger25 which ts closely within the cylinder 26, which is attached to anddepends from the tool joint above. 'Ihe lower end of the plunger 25 `isconnected to the upper end of the sleeve I6 in any suitable manner,preferably by threads.

The upper end of the rod 24 is formed with a conical shaped-head 21 fora purpose to be hereafter stated.

The lower` .end 'of the cylinder 26 is provided with an internal annulardownwardly facing shoulder 28.

In carrying on drilling operations when it is desired to take the core,the core taking apparatus may beasseinbledas shown and a suitablegrapple attached to .the head 2l and the apparatus let down through thedrill stem by means of a cable attached to the-grapple. The lower end ofthe core barrel 6 will enter the enlarged upper end of the bore 4 andthe plungers will enter the corresponding tool joints 2 and the drillingiiuid above under pump pressure will force said plunger downwardlythrough the cylinders. While the coring apparatus is being so loweredthe pin I8-will hang on the lower ends of theslots I1 and if for anyreason the lower end of the core barrel 6 should hang in the bore 4, thepressure of the uid above the plunger 25 will force said plungerdownwardly, the sleeve I6 moving downwardly on the anchor I6 until theupper ends of the slots I1 engage the ends of the pin I8 and the stem 8and barrel 6 will be forced further down until the core barrel is forcedinto home position whereupon the plungers 25 and 9 will clear therespective outlet ports 29, 30 in the respective cylinders 26, and I 0.Thereupon the pressure being released kthe pump will speed up indicatingthat thecore barrel has landed on the seat 5.

While the coring apparatus is being lowered, the sleeve 'I6 will be inits upper position relative to the anchor I5 as hereinabove indicatedand the spring dogs 2I will be thereby held in inner, or retracted,position, lbut when the sleeve I6 has been moved downwardly relative tothe' anchor I5, as above indicated, the slot 20 will align with the sideslots 3|, 3I, through the sleeve I6 and the upper ends of the dogs 2|,2I will be projected through and beyond said slots 3| and when saidupper ends clear the shoulder 28 they will engage underneath theshoulder 28, to lock said core barrel in place.

The grapple may then be detached from the head 21 and the cable removedand drilling may then be proceeded with. A core or sample of theformation will enter the bore 4 and pass up into the core barrel above.-Any liquid that may be in said core `barrel will pass out through theseat I2 the valve I4 lifting for that purpose and said liquid will passon out through Vthe openings II. While the core is being taken drillingfluid will be forced under pressure down through the drill stem and willpass out through the channels 32, 32 which lead from said drill stem anddiverge through the drill 3 whereby flushing fluid is discharged infront of the respective cutter blades, or other cutters 33, 33 .1

The lower end of the drill may be formed with a pilot core bit 34 of anyselected design.

When a core or sample has been taken the grapple may be again lowered asbefore andengaged over the head 21. An upward pull on the cable willcause the sleeve I6 to move upwardly relative to the anchor I5 and theupward moveto the ground surface for an inspection of the core.

The drawing and description discloses what is now considered to be apreferred form of the invention by way of illustration only while thebroad principle of the invention will be defined by the appended claims.

What I claim is:

l. A core taking apparatus comprising a tubular drill stem having adrilling tool at the lower end thereof provided with an axial borehaving an upwardly facing seat, spaced cylinders in the stem each havingan inlet, a core barrel in the stem whose lower end is adapted to reston said seat, spaced plungers connected to the barrel arranged to entersaid cylinders as the barrel is lowered, said plungers forming means bywhich the barrel may be forced downwardly onto said seat by the pressureof the drilling fluid above and being arranged to clear said inlets whenin home position.

2. A sample taking apparatus comprising a tubular drill stem havingupper and lower cylinders therein, a drill on the lower end of said stemhaving an inlet for the entrance of a sample, a core barrel shaped to belowered through said stem and cylinders into cooperating relation withthe drill and into alignment with the inlet, plungers connected withsaidbarrel and arranged to enter the respective cylinders as the barrelapproaches its final position in the stem whereby pressure fluid in thestem above the plungers may be rendered effective to force the barreldownwardly to its final position, each cylinder having an outlet portand said plungers being positioned to clear said ports to release saidpressure when the barrel reaches said nal position.

3. A sample taking apparatus comprising a tubular drill stem havingupper and lower cylinders therein, a drill on the lower end of said stemhaving an inlet for the entrance of a sample, a core barrel shaped to belowered through said stem and cylinders into cooperating relation withthe drill and into alignment with the inlet, plungers connected withsaid barrel and arranged to enter and completely close the respectivecylinders as the barrel approaches its final position in the stemwhereby pressure uid in the stem above the plungers may be renderedeffective to force the barrel downwardly to its nal position, saidplungers having a slip joint connection formed with relatively movableparts and interengaging means carried by said stem and connectionrespectively and normally locking the barrel in the stem, said lockingmeans being arranged to be released upon the relative movement of saidparts.

FRED THRIFI.

